2024 YZ125 Vet A rider Build to a 137cc

So, I've never been a fan of big bore 125s up to a 134 or 144!  They run out of power way too soon and if you're on a 125, you don't want to run out of power too soon at all! In fact, you want what little you have to last as long as possible and the bike to keep pulling....!

Back in 2013 I was at a KTM ride day at a local track and I LOVED the 150! I remember thinking "this is what a works 125 must feel like to those Pros who are blessed to race 'Factory' bikes!" It was incredible! It hit hard off the bottom and pulled to the moon....  I wanted one! Plenty of Want, short on Cash....  Never got one. Fast forward, a couple of years ago I rode a buddy's new SX150 and it was slow and ran out of power almost instantly.  Big disappointment! Come to find out, the 2013 that I loved had a longer crank to go along with the bigger piston. A few months ago MXA is testing Pasha's YZ155 (bored and stroked) and loving it!  So, my version with JM Racing's help is a 137. 2mm big bore with a 1mm stroke! So far it is fantastic. Reminds me of the '13 150SX....  Pulls strong off the bottom and keeps revving till you're ready for the next gear.  

We went with Crank works for the Stroke and with Ratt Racing for the 2mm over bore. Both came back looking great and I was very pleased. Of course I had John doing his magical porting on the cylinder to matych the bigger bore and longer reach of the crank, he modded the head to accompany the 137cc program, gave it some more fuel,and we're off to the races!  

Got a little video below, check it out.